FRIDAY, July 10, 2015 (HealthDay News) -- Close relatives and even the spouses of people with celiac disease appear to face a raised risk for other types of autoimmune disorders, a new analysis suggests.
Autoimmune disorders arise when the immune system launches an attack on the body's own tissue.
"The prevalence of celiac disease in first-degree relatives of individuals with celiac is approximately 10 percent," said study author Dr. Louise Emilsson, of Oslo University in Norway.
"Despite these findings, little is known about the risk of non-celiac autoimmune disease in these individuals," she said in a news release from the American Gastroenterological Association. "We found convincing results that close relatives are also at risk for these conditions, but more surprisingly, we found that spouses may also be at risk."
Celiac disease is a digestive disorder. It interferes with absorption of nutrients from food and damages the small intestines. People with the disease cannot tolerate gluten, a protein found in wheat, rye and barley.
The researchers analyzed data collected by Sweden's national medical registry and focused on the risk for developing a wide range of autoimmune disorders, from Crohn's disease to type 1 diabetes and rheumatoid arthritis.
The risk for such disorders was explored among more than 84,000 fathers, mothers, siblings and children of celiac patients -- all considered first-degree relatives -- and spouses. They were tracked for an average of almost 11 years, and their risk profiles were compared with those of nearly 431,000 men and women who had no close relationship with a celiac patient (the "control" group).
The result: more than 4 percent of the close relatives developed a non-celiac autoimmune disorder. This compared with just a little more than 3 percent of the control group.
Although the study found an association between having a close relative with celiac disease and risk of developing an autoimmune disorder, the link seen in the study does not prove a cause-and-effect relationship.
The explanation may be partly genetic and partly environmental, the researchers suggested. It's also possible that people close to celiac patients may be more likely to seek medical attention for autoimmune disorders -- or that doctors who know of the celiac patient are more likely to look for autoimmune disorders in their family members.
Lupus, type 1 diabetes and sarcoidosis (an inflammatory disease) were the most common non-celiac autoimmune diseases seen, the study authors said.
The findings appear in the July issue of Clinical Gastroenterology and Hepatology.
For more on celiac disease, see the U.S. National Institute of Diabetes and Digestive and Kidney Diseases.